GOODWILL AND OTHER INTANGIBLE ASSETS (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Changes in the carrying amount of goodwill for each of the company's reportable segments
Impairment of goodwill	$ 0.0
Changes in the carrying amount of goodwill
Beginning goodwill	8,012.7
Effect of foreign currency translation	49.5
Ending goodwill	8,062.2
Future estimated amortization expense related to amortizable other identifiable intangible assets
Estimated expense for the remaining nine-month period	223.0
Total amortization expense related to other intangible assets	75.6	$ 79.5
Nalco Holding Company ("Nalco") \| Trademarks
Changes in the carrying amount of goodwill
Impairment of indefinite life intangible asset	0.0
Global Industrial
Changes in the carrying amount of goodwill
Beginning goodwill	4,081.8
Effect of foreign currency translation	30.7
Ending goodwill	4,112.5
Global Institutional and Specialty
Changes in the carrying amount of goodwill
Beginning goodwill	567.6
Effect of foreign currency translation	1.5
Ending goodwill	569.1
Global Healthcare and Life Sciences
Changes in the carrying amount of goodwill
Beginning goodwill	3,125.4
Effect of foreign currency translation	16.4
Ending goodwill	3,141.8
Other
Changes in the carrying amount of goodwill
Beginning goodwill	237.9
Effect of foreign currency translation	0.9
Ending goodwill	$ 238.8

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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